Conventional methods for creating nanofibrillated cellulose or nanocellulose are typically high energy processes or processes involving manipulating the cellulose to allow a reduction in energy consumption, such as partial derivatisation of the cellulose (see e.g. U.S. 2011/0036522), the use of an inorganic acid (see, e.g. Cellulose (1998) 5, 19-32), the use of alkaline processes or enzymes or a combination of these, or combining pulp with a cellulose derivative prior to processing to reduce energy requirements (see, e.g. U.S. 2012/0043039)
Applicants have now discovered a new low energy method for the preparation of non-derivatized nanocellulose via a swollen intermediate stage.